Although its been raging for more than a year now, the social music battle heated up even more today with the launch of Soundrop for iOS, a group listening app built using Spotify’s API.

Back in November, Spotify announced plans to include a series of third-party apps within its desktop service as part of the newly coined “Spotify Platform.” Soundrop was one of the first apps — and one of our favorites.

The app is a kind of grownup version of Turntable.fm — it lacks avatars and gameplay, simply allowing users to listen to tunes with other Spotify denizens. Soundrop.fm is its mobile iteration.

Upon firing up the iOS version (you’ll need Facebook and Spotify Premium on your device), it becomes immediately apparent that it’s a stripped-down offering when compared to the desktop incarnation. You’re presented with a list of rooms — with no search function — covering genres from black metal to reggae. Enter a room to start listening to tunes chosen by other Soundrop users, add your own jams to the room playlist, vote for songs that you want to hear, and to chat with other users.

Pretty cool, no? Well, sure, but the in-Spotify app is undoubtedly cooler. For one thing, you can create your own rooms in that version, a boon to those who want a more intimate listening experience (some pre-made rooms have more than a thousand listeners, which means it might be a while before you can listen to that Coldplay song you added). To host your own room within the app, you’ll have to create it via the desktop version first.

Also, via the app you can share a room link via email, SMS or social channels, but you can’t — as in the in-Spotify version — save the whole room as a playlist. That function would be nice to include, as it’s a good way to bookmark music that you discover during your listening session.

All in all, we’re going to give Soundrop.fm a solid “good start,” as we imagine that the team will roll out some updates pretty soon. It also has a pretty strong userbase already, with 225,000 active users according to CEO Inge Sandvik, so there’s no shortage of people to listen with.

Still, the newly minted app is entering a battle field where a cadre of similar services are already warring: Namely Turntable.fm for mobile (with all four major labels in tow) and Myxer Social Radio, a relative David to Spotify and TT.fm’s Goliath (it has around 150,000 active users), but still a pretty solid offering.